Lattice/Lattice.UI.Docking.WinUI/Controls/LatticeDockGroup.cs

using Lattice.Core.Docking.Abstractions;
using Lattice.Core.Docking.Engine;
using Lattice.Core.Docking.Models;
using Lattice.UI.Docking.Abstractions;
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
using System;
using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace Lattice.UI;

public sealed class LatticeDockGroup : Control, IDockGroupControl, IDisposable
{
    private readonly PropertyChangedEventHandler _modelPropertyChangedHandler;
    private bool _disposed;
    private DockGroup? _model;
    private Grid? _rootGrid;
    private ContentControl? _firstChildControl;
    private ContentControl? _secondChildControl;
    private LayoutManager? _layoutManager;
    private IDockContextManager? _contextManager;
    private bool _isSelected;
    private bool _isActive;
    private double _splitRatio = 0.5;
    private double _splitterSize = 4.0;

    public LatticeDockGroup()
    {
        this.DefaultStyleKey = typeof(LatticeDockGroup);
        _modelPropertyChangedHandler = OnModelPropertyChanged;
        this.DataContextChanged += OnDataContextChanged;
    }

    public IDockElement? Model
    {
        get => _model;
        set
        {
            if (_model == value) return;
            DetachModel();
            _model = value as DockGroup;
            AttachModel();
            OnPropertyChanged(nameof(Model));
        }
    }

    public LayoutManager? LayoutManager
    {
        get => _layoutManager;
        set
        {
            if (_layoutManager == value) return;
            _layoutManager = value;
            OnPropertyChanged(nameof(LayoutManager));
        }
    }

    public IDockContextManager? ContextManager
    {
        get => _contextManager;
        set
        {
            if (_contextManager == value) return;
            _contextManager = value;
            OnPropertyChanged(nameof(ContextManager));
        }
    }

    public bool IsSelected
    {
        get => _isSelected;
        set
        {
            if (_isSelected == value) return;
            _isSelected = value;
            OnPropertyChanged(nameof(IsSelected));
        }
    }

    public bool IsActive
    {
        get => _isActive;
        set
        {
            if (_isActive == value) return;
            _isActive = value;
            OnPropertyChanged(nameof(IsActive));
        }
    }

    public bool CanDrag => true;
    public bool CanDrop => true;

    public SplitDirection Orientation
    {
        get => _model?.Orientation ?? SplitDirection.Horizontal;
        set
        {
            if (_model != null && _model.Orientation != value)
            {
                _model.Orientation = value;
                UpdateLayoutDefinitions();
            }
        }
    }

    public double SplitRatio
    {
        get => _splitRatio;
        set
        {
            if (Math.Abs(_splitRatio - value) > 0.001)
            {
                _splitRatio = value;
                UpdateLayoutDefinitions();
                OnPropertyChanged(nameof(SplitRatio));
                SplitRatioChanged?.Invoke(this,
                    new SplitRatioChangedEventArgs(value, SplitRatioChangeSource.Programmatic));
            }
        }
    }

    public double SplitterSize
    {
        get => _splitterSize;
        set
        {
            if (Math.Abs(_splitterSize - value) > 0.001)
            {
                _splitterSize = value;
                OnPropertyChanged(nameof(SplitterSize));
            }
        }
    }

    public IDockControl? FirstChild => _firstChildControl?.Content as IDockControl;
    public IDockControl? SecondChild => _secondChildControl?.Content as IDockControl;

    public event EventHandler<SplitRatioChangedEventArgs>? SplitRatioChanged;
    public event PropertyChangedEventHandler? PropertyChanged;

    protected override void OnApplyTemplate()
    {
        base.OnApplyTemplate();

        _rootGrid = GetTemplateChild("PART_Grid") as Grid;
        _firstChildControl = GetTemplateChild("PART_First") as ContentControl;
        _secondChildControl = GetTemplateChild("PART_Second") as ContentControl;

        UpdateLayoutDefinitions();
    }

    private void OnDataContextChanged(FrameworkElement sender, DataContextChangedEventArgs args)
    {
        Model = args.NewValue as DockGroup;
    }

    private void AttachModel()
    {
        if (_model != null)
        {
            _model.PropertyChanged += _modelPropertyChangedHandler;
            this.DataContext = _model;
            _splitRatio = _model.SplitRatio;
            UpdateLayoutDefinitions();
        }
    }

    private void DetachModel()
    {
        if (_model != null)
        {
            _model.PropertyChanged -= _modelPropertyChangedHandler;
            this.DataContext = null;
        }
    }

    private void OnModelPropertyChanged(object? sender, PropertyChangedEventArgs e)
    {
        switch (e.PropertyName)
        {
            case nameof(DockGroup.Orientation):
                OnPropertyChanged(nameof(Orientation));
                UpdateLayoutDefinitions();
                break;

            case nameof(DockGroup.SplitRatio):
                if (_model != null)
                {
                    _splitRatio = _model.SplitRatio;
                    OnPropertyChanged(nameof(SplitRatio));
                    UpdateLayoutDefinitions();
                }
                break;
        }
    }

    private void UpdateLayoutDefinitions()
    {
        if (_rootGrid == null || _model == null) return;

        _rootGrid.ColumnDefinitions.Clear();
        _rootGrid.RowDefinitions.Clear();

        if (_model.Orientation == SplitDirection.Horizontal)
        {
            _rootGrid.ColumnDefinitions.Add(new ColumnDefinition
            { Width = new GridLength(_model.SplitRatio, GridUnitType.Star) });
            _rootGrid.ColumnDefinitions.Add(new ColumnDefinition
            { Width = GridLength.Auto });
            _rootGrid.ColumnDefinitions.Add(new ColumnDefinition
            { Width = new GridLength(1 - _model.SplitRatio, GridUnitType.Star) });

            if (_firstChildControl != null)
            {
                Grid.SetColumn(_firstChildControl, 0);
                Grid.SetRow(_firstChildControl, 0);
            }

            if (_secondChildControl != null)
            {
                Grid.SetColumn(_secondChildControl, 2);
                Grid.SetRow(_secondChildControl, 0);
            }
        }
        else
        {
            _rootGrid.RowDefinitions.Add(new RowDefinition
            { Height = new GridLength(_model.SplitRatio, GridUnitType.Star) });
            _rootGrid.RowDefinitions.Add(new RowDefinition
            { Height = GridLength.Auto });
            _rootGrid.RowDefinitions.Add(new RowDefinition
            { Height = new GridLength(1 - _model.SplitRatio, GridUnitType.Star) });

            if (_firstChildControl != null)
            {
                Grid.SetRow(_firstChildControl, 0);
                Grid.SetColumn(_firstChildControl, 0);
            }

            if (_secondChildControl != null)
            {
                Grid.SetRow(_secondChildControl, 2);
                Grid.SetColumn(_secondChildControl, 0);
            }
        }
    }

    public void SetChildren(IDockControl? firstChild, IDockControl? secondChild)
    {
        if (_firstChildControl != null)
            _firstChildControl.Content = firstChild;

        if (_secondChildControl != null)
            _secondChildControl.Content = secondChild;

        UpdateLayoutDefinitions();
    }

    public object? PrepareDragData()
    {
        return Model;
    }

    public bool HandleDrop(object data, DockPosition position)
    {
        // TODO: Реализовать обработку сброса
        return false;
    }

    public void Refresh()
    {
        UpdateLayoutDefinitions();
    }

    public void ApplyTheme(IDockTheme theme)
    {
        // TODO: Реализовать применение темы
    }

    public void OnModelPropertyChanged(string propertyName)
    {
        if (_model != null)
        {
            OnModelPropertyChanged(_model, new PropertyChangedEventArgs(propertyName));
        }
    }

    private void OnPropertyChanged([CallerMemberName] string? propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    public void Dispose()
    {
        if (!_disposed)
        {
            DetachModel();
            _disposed = true;
            GC.SuppressFinalize(this);
        }
    }
}